Insole



July17,1934. H HVRTL .1,966,719

INSOLE Filed Jan. 22. 1932 .7M A/W im Patented' July 17, 1934 msoLE Y Hans Hrtl, Berlin, Germany kApplication January z2, 1932, serial No. 588,109 In Germany February 11, 1931 2 Claims. (C1. 36-22) `This invention relates to a method for producing insoles and for padding shoes which are manufactured either according to the gluing process, the stitching process (Mackay) 4or the 5 welt process (Goodyear). The process according to the invention is suitable for making the insole or shoe absolutely ex'ible besides possessing other advantages.'

According to the invention the .front portion l0 of the insole for the gluing process, which consists of a'particularlyv thin leather layer and a thin leather strip extending along the edge, is united by an interposed elastic intermediate layer which preferably extends in knownmanner over an elastic filling mass for the shoe already contained in the insole. 1

The invention and the novelty in its fundamental idea consist in that an ordinary leather insole is split at its front end, and between these two leather portions which, owing to their slight thickness, are necessarily flexible, an elastic intermediate layer such as rubber is inserted so that the iiexibility of the two leather parts is retained and the insole nevertheless offers sufflcient durability and resistance during the working. This is based on the following considerationz A leather sole about 2 to 3 mms. in thickness, such as is generally employed for insoles, is stiff and brittle. If this leather sole is split into two layers of uniform thickness, each of these two'layers is exible and elastic but does not 'offer suliicient resistance to allow of work- Wing to form an insole. If for example a thin rubber layer is inserted between these two layers, the exibility of the entire arrangement remains, because the two leather layers, in spite of being intimately connected by the rubber layer, can always shift relatively according to the elasticity of the rubberemployed.

'I'he elasticintermediate layer preferably extends in known manner over thelling which consists of a porous sponge rubber-like mass.

, The filling mass is directly connected to the intermediate layer, whereas it isonly in loose contact with the leather layer.

The insole according to the invention offers the following advantages:

5 It is extremely flexible, it is not heavy, it prevents the penetration of all moisture, it is easy to produce, and it is strong. Moreover,

subsequent filling of the shoe during the manu` facture is avoided by this insole.

55 An embodiment of the invention is illustrated by way of example in the accompanyingdrawing. in whichzy Fig. 1 shows an insole in bottom plan view.

Fig. 2 is a section on line 1I'-]I of Fig. 1.

The insole serving for use for the gluing or Mackay process consists of a leather layer a which is either continuous or, as is known, composed of two parts connected along the broken line C-D. The middle portion of the leather layer a is loosely connected to a porous rubber sponge-like filling mass b, which is stuck to the elastic intermediate' layer c and extends up to the edge of the sole. On this -solid rubber layer c a leather strip d extendingA along the edge is iixed and either made in one piece or divided on the broken line E-F.

The insole according to the invention may be produced inthe following manner: A leather insole about 3'mms. in thickness is stamped in the usual' shape, trimmed,A scoured and split 75 at the front end up to the shank, so that a layer of about 1 mm. in'thickness remains on the sole, whereas a second layer about 1 mm. in thickness drops olf. The edge strip, about 12 to 15 mms. in Width, is stamped out of the 8,0 upper split. The filling mass and a solid rubber sole, about 0.5 mms. in thickness, are then stamped out. The parts are itted together in the following manner:-

The elastic cover c, which is directly connected to the porous filling b, is stuck on the front portion of the insole along the edge of the leather layer a. by means of its edge strip'. The leather strip d is then stuck on to the solid rubber layer c along its edge.

The leather strip d is provided in order to enable the insole to-be employed for the gluing process andV also in order to impart a certain strength to the insole. The advantages of such a method for producing insoles and for lling foot wear for the gluing and Mackay processes are the following-f Y The exibility is obtained by splitting the front portion a and introducing the elastic intermediate layer c. The lling b, which is only in loose contact with the leather layer a, does not impair the elasticityv of the insole. During the manufacture the shoe or the filling need not be subjected to a. long drying process, so that the shoe can be manufactured in a much shorter time than hitherto. Owing to the connection of the lling b and the rubber layer c which extends over the entire area of the insole, moisture is prevented from penetrating. The employment of such an elastic lling b also presents the advantagethat the insole, which isv itself elastic, has an orthopedic effect and adapts itself plastically to the foot. Owing to the employment of rubberl the pressure exerted by the foot is to a great extent absorbed, so that the outer sole is o nLv subjected to slight wear.

.No increase'in weight is caused, as the porous filling mass b together with the' thin elastic layer c do not weigh more than the illling masses hitherto known. As the foot does not come -into direct contact with the rubber, excessive splitting off the front portion of an ordinary leather insole, producing an'edge strip from the portion cut oif by the splitting, inserting a porous rubber sponge-like lling mass in the spaces surrounded by the leather edge strip, and inserting an elastic intermediate layer between the leather edge strip and the inner sole, said intermediate layer being positively connected' to the insole and the edge strip and extending preferably over the filling mass.

2. An insole comprising in combination a piece of leather cut to the shape of the insole and thinned at its front portion, a. thin leather strip extending around the thinned portion of said leather piece, a porous rubber sponge-like filling mass in the space surrounded by said strip, and an elastic intermediate layerbetween said stripand said leather piece extending over and covering said lling mass. H

HANS HAR'I'L. 

